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Resonantly-Produced 7 keV Sterile Neutrino Dark Matter Models and the Properties of Milky Way Satellites

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 نشر من قبل Kevork Abazajian
 تاريخ النشر 2014
  مجال البحث فيزياء
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Sterile neutrinos produced through a resonant Shi-Fuller mechanism are arguably the simplest model for a dark matter interpretation origin of the recent unidentified X-ray line seen toward a number of objects harboring dark matter. Here, I calculate the exact parameters required in this mechanism to produce the signal. The suppression of small scale structure predicted by these models is consistent with Local Group and high-$z$ galaxy count constraints. Very significantly, the parameters necessary in these models to produce the full dark matter density fulfill previously determined requirements to successfully match the Milky Way Galaxys total satellite abundance, the satellites radial distribution and their mass density profile, or too big to fail problem. I also discuss how further precision determinations of the detailed properties of the candidate sterile neutrino dark matter can probe the nature of the quark-hadron transition, which takes place during the dark matter production.

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